Accountable2You originated as a personal replacement for other, slower, accountability software and has since blossomed into a product in its own right. The product site and product interface are quite nice.

CovenantEyes has a beautiful website with a lot of articles about pornography. The site seems to target porn addicts and concerned parents with roughly equal emphasis. The focus (and strength) of the software is accountability rather than filtering.

DansGuardian is a content filtering proxy that works in conjunction with another caching proxy such as Squid or Oops. It seems to be targeted primarily toward filtering internet content for organizations such as schools. A guide to setting it up for personal use can be found here.

Sold to companies for overlord-style filtering, Blue Coat allows free use of the filter for individuals looking to protect themselves or their family. It is configured using an administrative password. The k9 administrator can view all previous internet activity in addition to changing which categories to block and which features to enable.

A Firefox extension, the ProCon Latte Content Filter blocks (usually containing pornography) based on simple keyword lists. It supports password protection, and it can be configured to only allow whitelisted sites.

Qustodio appears to be a complete filtering/monitoring package. Aimed primarily at parents and schools, it boasts that its "smart internet filters scans web content in real time". There are some rumors it hampers the Internet experience of folks who have slow Internet connections.

The free version of x3watch is an accountability-based monitoring software package. The user provides the email address of a buddy who will be emailed reports summarizing the browsing history of the user. The paid version offers filtering as well as monitoring.

Net Responsibility monitors Internet usage and sends e-mail reports to accountability partners. Must be compiled from source on Mac OS X and Ubuntu 14.10 or above (see this thread). A build script can be found here.

e2guardian is a fork and continuation of DansGuardian. It is an open source web content filter that filters based on many methods including phrase matching, request header, URL filtering, etc. Unlike DansGuardian, e2guardian has some support for https filtering, if the necessary authoritative certificates are installed in the browser.

Net Angel sells home routers that have e2guardian pre-installed. Whenever a website is blocked, a text message is sent to a phone phone number. As of 2016-11-11, the company also has beta-quality iOS and Android apps that will feature similar techniques.

Parenteeno monitors what the user (i.e., child) does on the target device and sends the data to the Parenteeno servers where reports are prepared for parental review. The product is created by 2 dads in Dublin and the product page says it is all about protecting children from "cyberbullying, sexting, predators and other menace."

R|Tribe is an app for mobile devices that attempts to assist users in "interrupting the addiction cycle." Through in-app connections to friends (i.e., reports), and self-tracking of recovery, the user gains knowledge about their own addiction cycle and is assisted in finding ways to break it.

A URL redirector that can be used with the Squid proxy and that supports large blacklists (altough DansGuardian claims to be significantly faster). It has seen very little modification in recent years.

URLFilterService works with Internet Explorer and Microsoft Edge. It categorizes sites using Shalla Secure Service and Université Toulouse 1 Capitole url listings. The installation video shows that one must disable default Windows security in order to install it, and the FAQ says, "Use it at your own risk." Indeed.

Aimed at businesses, governments, and schools, ClearOS is designed to be installed on a router. clearOS sells switches with ClearOS installed and calls them "appliances". It is very similar to DansGuardian.

A general Internet user who finds themselves too often distracted by the Internet. Similar to but different from the addict.

spouse

A spouse of a porn addict if the addict himself does not want to stop using porn. This audience is not categorized on this page. See instead parent or overlord.

Platform Legend

ailing

The software is not actively maintained and may or may not still be functional.

android

The software integrates with Android.

chrome

The software integrates with Chrome and/or Chromium.

browser

The software integrates with one or more browsers (e.g., Chrome, Firefox, Internet Explorer, Opera, Safari) as opposed to the operating system or network.

firefox

The software integrates with Firefox.

ios

The software integrates with iOS.

linux

The software integrates with Linux.

macosx

The software integrates with Mac OS X.

network

The software integrates with a network device, usually as opposed to a browser or operating system. Such software is typically installed on a router, but can sometimes be installed on the local machine if the operating system is of the right kind. All gateways and proxies work at the network level.

windows

The software integrates with Windows.

Feature Legend

abandoned

The software has not been updated for a long time and may not work on modern operating systems.

accountability

The software notifies an accountability partner, parent, or spouse regarding Internet activity or filter configuration, typically over email but sometimes using another means such as RSS.

antivirus

The software is part of an antivirus product. Most antivirus products come with some type of parental controls.

applock

The software can block user access to programs. See also games.

biglist

Filtering is accomplished through a large database of categorized resources.

changedelay

The software allows the end-user to configure it without a password, but will not allow the change to take effect for some amount of time. The author knows of no filter that supports this other than Pluckeye.

cloud

The software interacts with data in the cloud. E.g., a list of websites to block are retrieved from a remote server.

countermeasures

The software will notice and respond to attempts to work around it. E.g., k9 can be configured to block all Internet access for a specified time if too many attempts to visit blocked pages are detected.

filtering

The software blocks some content. There are several kinds of filtering.

games

The software can block user access to other programs (typically this is used to limit game time).

gateway

The software is meant to be installed on a network router separate from the end-user machine. In the case of a gateway filter on this page, the OS value lists all operating systems to reflect the fact that the end-user machine may have any operating system. Such software is typically created for schools and employers.

hardware

The software comes preinstalled on a device that connects to and filters for the local network.

harvester

The software harvests data from the user for the benefit of the publisher of the software. This designation is hard to determine with certainty because what exactly is done with data sent to the software publisher known only to the publisher.

incomplete

The software describes itself as incomplete.

keyword

Filtering is accomplished on the fly through keyword detection within web pages.

locationtracking

The location of the end-user is tracked and usually presented to another person (ostensibly the end-user's parent).

mimetypes

Filtering can be done on a mime type basis. E.g., Pluckeye can block all images from http://craigslist.org/ , but still allow text.

monitoring

The software monitors Internet activity or filter settings for the purpose of allowing a parent, accountability partner, or other person to view. See also accountability.

more

The software has other features that do not fit one of the other feature categories.

motivate

The software has motivational messages for the end-user.

opensource

The software is open source.

opensource-contrib

The software is open source to interested contributors.

password

The software allows or requires configuration to be protected by a password.

The software can detect profane words and replace them with #$@! characters.

proxy

The software is a proxy and requires browsers be configured to use it (note that this meaning is specific to this page). See also gateway for another kind of proxy.

ratings

The software uses self-identifying website ratings such as as RTA and SafeSurf or the discontinued PICS or POWDER labeling systems.

screenshots

The software takes screenshots so that some other person can review what the user was doing.

skin

The software uses computer vision techniques to dynamically recognize skin in images. See also pixelation.

smarts

The software tries to determine whether content should be allowed or not by examining content. This is sometimes used in combination with biglist techniques and sometimes as an alternative.

social

The software specifically monitors interaction on social media sites such as Facebook, Google+, Instagram, LinkedIn, Pinterest, Tumblr, and Twitter, etc., with the intent of informing a parent about how their child is interacting through these sites.

spying

The software spies on the user and generates reports for somebody else to look at. Spying is similar to monitoring and accountability but distinct because filters that do spying are more invasive, often they go so far as to log key strokes.

timer

The software can be configured to enable or disable access to the Internet or parts of the Internet for a specified amount of time or time of day.